(1) Field of the Invention
The present invention relates to a pitch sensor system and more particularly to a very small sensor that, in combination with a sensing circuit, measures angular rotation about the pitch axis while remaining insensitive to angular rotations about the yaw or roll axis.
(2) Description of the Prior Art
It is well known that there are commercially available sensors which use a mass on the end of a pendulum, the rotating shaft at the upper end of the pendulum being geared to a resistance potentiometer which then varies resistance in proportion to roll induced pendulum motion. Vertical gyros and inertial platforms have also been used to sense motion about a vertical axis. Also, electrolytic switches have been used to sense tilt. Both the pendulum devices and the gyros and inertial platforms devices are very large. In addition, the pendulum is undesirable in that it responds to cross axis motion while the gyros and inertial platforms are very complicated and expensive devices. The electrolytic switch devices sense only discrete tilt values, typically providing a constant signal when tilted from a preset state through any angle.